4-Rotor FC Build
11-02-12, 06:25 PM
#1053
i just had an idea...
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
Last edited by RotaryEvolution; 11-02-12 at 06:37 PM.
11-03-12, 05:13 AM
#1058
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Been watching this build on and off since the beginning. Wonderful stuff going on. I must say it's nice to see the chassis and body coming together now. Keep on it dude.
11-04-12, 06:02 PM
#1061
S4 / S5 TII
Why go trough all the trouble adapting a second cas? Isn't it easier to just add an external triggerwheel, fabricate 2 brackets, and just fit 2 sensors? I'm also running an external triggerwheel. Anyway I don't see the need for running 2 ecu's, even if you really want to use split timing there are ecu's that can do it, Hell, I think even megasquirt can do it.
That's not such a bad idea really
Update
Today was a slow rainy sunday, so I locked myself up in the machine shop and started making shiny suspension parts
I started with the lower control arms, those flexy rubber bushings had to go, I'm going with bearings!
Couldn't finish it today though
, the lower control arms themselves also need a little bit of machining, but they are a little bit too big for my lathe, it was really close though. Ah well, I'll take them over to my buddy who has a bigger lathe soon. In the meantime I'm drawing up more parts, in this case camberplates, since my coilovers don't have them. I could probably also get these from tein or somewhere but where's the fun in that
i just had an idea...
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
Why go trough all the trouble adapting a second cas? Isn't it easier to just add an external triggerwheel, fabricate 2 brackets, and just fit 2 sensors? I'm also running an external triggerwheel. Anyway I don't see the need for running 2 ecu's, even if you really want to use split timing there are ecu's that can do it, Hell, I think even megasquirt can do it.
That's not such a bad idea really
Update
Today was a slow rainy sunday, so I locked myself up in the machine shop and started making shiny suspension parts
I started with the lower control arms, those flexy rubber bushings had to go, I'm going with bearings!
Couldn't finish it today though
, the lower control arms themselves also need a little bit of machining, but they are a little bit too big for my lathe, it was really close though. Ah well, I'll take them over to my buddy who has a bigger lathe soon. In the meantime I'm drawing up more parts, in this case camberplates, since my coilovers don't have them. I could probably also get these from tein or somewhere but where's the fun in that
11-05-12, 11:45 AM
#1065
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i just had an idea...
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
early 12A twin dizzy front cover modified to accept 2 FC crank angle sensors. would allow you to run all 8 ignition circuits induvidually for poper leading/trailing including split.
i just happen to have one sitting here, the CAS fits fine but would need a timing lock tab welded on. i will have to check the depth but spacer rings could probably be made easy enough if it isn't just right.
figure this may be one option i use and just run 2 microtech units, treating the engine as 2 separate halves.
wish i had more time to work on the damn thing though!
that white JC cosmo with the 20B PP engine is running THREE power FC's... the japanese LOVE that ecu...
11-05-12, 05:07 PM
#1066
John, have you seen how Supernow approached that bushing? Are you just replacing the entire width of the original bearing?
Supernow Link
Supernow Link
. Anyway I'm thinking about switching to spherical bearings, no problems with misaligning and it's proven to work well., they must really love those ecu's.
11-05-12, 05:20 PM
#1067
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11-05-12, 05:30 PM
#1068
most ECUs haven't adopted the 4 rotor platform and don't have the capability to run all 8 ignition channels with the split. i was just thinking about it and figured it was an option. i don't see a problem running 2 ECUs though if it could be done with a single ECU that's great.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
11-06-12, 12:14 PM
#1069
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most ECUs haven't adopted the 4 rotor platform and don't have the capability to run all 8 ignition channels with the split. i was just thinking about it and figured it was an option. i don't see a problem running 2 ECUs though if it could be done with a single ECU that's great.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
11-06-12, 12:16 PM
#1070
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11-06-12, 04:39 PM
#1071
. I wonder if they also used 3 programming laptops and 3 tuners to tune it 
most ECUs haven't adopted the 4 rotor platform and don't have the capability to run all 8 ignition channels with the split. i was just thinking about it and figured it was an option. i don't see a problem running 2 ECUs though if it could be done with a single ECU that's great.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
i'm just thrifty like that, having an LT8 already another would be cheaper than some of the pricey units that could do the job. i'd hate to be knee deep in and have some issues that required everything to go back to the drawing board while all the shiny bits collect dust.
, maybe even something I can do on my engine!... dammit, Yeah I know about the fit, I machine bearing holes all the time. If it's for something fancy or special I'll look up the required tolerances but most of the times I try to keep a +0 to +0.02mm tolerance, so for a 35mm bearing I machine the hole to be between 35.00mm and 35.02mm. 35.03mm or bigger get's scrapped or assembled with locktide depending on what it is.
11-06-12, 05:18 PM
#1072
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11-07-12, 05:08 PM
#1074
a single CAS could be used if the rotor phasing was the same, but a 90* phased engine would require 2 separate inputs for TDC, a trigger wheel would probably be best but the microtech doesn't support it... i doubt i will use the microtech units given that the CAS idea was pitched out the window. as you said it would be much simpler to run a single ECU for making any adjustment.
if it were phased to fire 2 rotors at the same time it would be so much simpler but i don't want to go through the effort for that setup on the engine.
if it were phased to fire 2 rotors at the same time it would be so much simpler but i don't want to go through the effort for that setup on the engine.
11-08-12, 09:29 AM
#1075
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Microtech supports some trigger wheel functions, I think they started allowing use of the RX-8 trigger wheels in 13B's, and they sell crank trigger kits for different models. You could use dual 180* offset trigger wheels if you really wanted to use the 2 LT's, or ask them about programming for a custom one.
Once again John, build is looking great! If you decide to save yourself some labour, you could go with the ground control camber plates:
They seem to be a well-built unit, I have some for my FC.
Once again John, build is looking great! If you decide to save yourself some labour, you could go with the ground control camber plates:
They seem to be a well-built unit, I have some for my FC.